Vessel cutting devices

ABSTRACT

A catheter-based system for accessing specific body cavities percutaneously and minimizing patient trauma is provided. In the preferred embodiment, in order to create an aperture at an access site in a patient&#39;s existing tubular body organ structure, a delivery sheath is passed axially along the interior of a portion of the existing tubular body organ structure to place a distal end of the delivery sheath near the access site. A centering wire is passed axially along the interior of the delivery sheath, piercing through from inside to outside of the patient&#39;s existing tubular body organ structure at the access site by causing an end portion of the centering wire to emerge from the distal end of the delivery sheath. A cutting catheter is passed substantially coaxially over the centering wire and axially along the interior of the delivery sheath. The aperture is formed by advancing a distal end of the cutting catheter through from inside to outside of the patient&#39;s existing tubular body organ structure at the access site and advancing the distal end of the delivery sheath through from inside to outside of the patient&#39;s existing tubular body organ structure at the access site.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This is a continuation of application Ser. No. 09/850,021, filedMay 7, 2001, which is a continuation of application Ser. No. 09/014,759(now U.S. Pat. No. 6,416,527), filed Jan. 28, 1998, both of which arehereby incorporated by reference herein in their entireties.

BACKGROUND OF THE INVENTION

[0002] This invention relates to vessel cutting devices for use in therepair, replacement or supplement of a medical patient's natural bodyorgan structures or tissues. More particularly, this invention relatesto vessel cutting devices for use in vascular anastomosis (the surgicalconnection of vessels).

[0003] An example of the possible uses of the invention is a minimallyinvasive cardiac bypass procedure. This and other examples areconsidered in detail in Goldsteen et al. U.S. Pat. No. 5,976,178, whichis hereby incorporated by reference herein in its entirety.

[0004] Vascular anastomosis is a delicate and time-consuming procedurein which fast and accurate vessel cutting plays a particularly importantrole.

[0005] In view of the foregoing, it would be desirable to provide acatheter-based system for accessing specific body cavitiespercutaneously, thereby minimizing patient trauma.

[0006] It would also be desirable to provide fast and accurate vesselcutting devices.

SUMMARY OF THE INVENTION

[0007] It is an object of the present invention to provide acatheter-based system for accessing specific body cavitiespercutaneously, thereby minimizing patient trauma. It is also an objectto provide fast and accurate vessel cutting devices.

[0008] These and other objects are accomplished by providing a methodand apparatus for creating an aperture at an access site in a patient'sexisting tubular body organ structure by passing a delivery sheathaxially along the interior of a portion of the existing tubular bodyorgan structure to place a distal end of the delivery sheath near theaccess site, passing a centering wire axially along the interior of thedelivery sheath, piercing through from inside to outside of thepatient's existing tubular body organ structure at the access site bycausing an end portion of the centering wire to emerge from the distalend of the delivery sheath, passing a cutting catheter substantiallycoaxially over the centering wire and axially along the interior of thedelivery sheath, forming the aperture by advancing a distal end of thecutting catheter through from inside to outside of the patient'sexisting tubular body organ structure at the access site and advancingthe distal end of the delivery sheath through from inside to outside ofthe patient's existing tubular body organ structure at the access site.

[0009] In one embodiment, the distal end of the cutting catheter isrotated to cut through the patient's existing tubular body organstructure at the access site. In another embodiment, a cutting catheterwith a conical (preferably star-shaped) cutting edge is pushed throughthe patient's existing tubular body organ structure at the access site.

[0010] The present invention can also be used to create an aperture inthe patient's existing tubular body organ structure by advancing adistal end of the cutting catheter through from outside to inside of thepatient's existing tubular body organ structure at the access site.

[0011] In the most preferred embodiment, all or substantially allnecessary apparatus is inserted into the patient via the patient'sexisting body organ vessel. In addition, all or substantially allapparatus functions are controlled by the physician (a term used hereinto also include supporting technicians) from outside the patient's body.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other objects and advantages of the invention willbe apparent upon consideration of the following detailed description,taken in conjunction with the accompanying drawings, in which likereference characters refer to like parts throughout, and in which:

[0013]FIG. 1a is a simplified sectional view showing the distal end of adelivery sheath in the interior of a portion of the existing tubularbody organ structure with a centering wire piercing through from insideto outside of the patient's existing tubular body organ structure at theaccess site;

[0014]FIG. 1b is a view similar to portions of FIG. 1a showing acentering wire piercing through from inside to outside of the patient'sexisting tubular body organ structure at the access site, wherein theend portion of the centering wire includes a selectively enlargeablestructure;

[0015]FIG. 1c is another view similar to portions of FIG. 1a showing acentering wire piercing through from inside to outside of the patient'sexisting tubular body organ structure at the access site, wherein theend portion of the centering wire includes fasteners;

[0016]FIG. 2 is yet another view similar to FIG. 1a showing a cuttingcatheter positioned for cutting at the distal end of a delivery sheathat the access site;

[0017]FIG. 3 is still another view similar to FIG. 1a showing formingthe aperture by advancing a distal end of the cutting catheter throughfrom inside to outside of the patient's existing tubular body organstructure at the access site;

[0018]FIG. 4 is yet another view similar to FIG. 1a showing advancingthe distal end of the delivery sheath through from inside to outside ofthe patient's existing tubular body organ structure at the access site;

[0019]FIG. 5 is a simplified elevational view, partly in section,showing the distal end of the cutting catheter advancing through fromoutside to inside to create an aperture in the patient's existingtubular body organ structure;

[0020]FIG. 6 is a side view of the patient's existing tubular body organstructure of FIG. 5, showing the aperture created;

[0021]FIG. 7a is still another view similar to FIG. 1a showing thedistal end of a delivery sheath in the interior of a portion of theexisting tubular body organ structure with a centering wire piercingthrough from inside to outside of the patient's existing tubular bodyorgan structure at the access site, wherein the cutting catheterincludes a dilator;

[0022]FIG. 7b is yet another view similar to FIG. 1a forming theaperture by advancing a distal end of the cutting catheter through frominside to outside of the patient's existing tubular body organ structureat the access site, wherein the cutting catheter includes a dilator;

[0023]FIG. 7c is still another view similar to FIG. 1a showing advancingthe delivery sheath through the aperture at the access site; and

[0024]FIG. 8 is yet another view similar to FIG. 1a showing a deliverysheath which includes distal and proximal selectively enlargeablestructures.

DETAILED DESCRIPTION OF THE INVENTION

[0025] As a preliminary step in creating an aperture at an access site10 in a patient's existing tubular body organ structure 1, a deliverysheath 20 is passed axially along the interior of a portion of tubularbody organ structure 1 to place a distal end of delivery sheath 20 nearaccess site 10. When the distal end of delivery sheath 20 is adjacent toaccess site 10, a centering wire 30 is passed axially along the interiorof the sheath until the end portion of centering wire 30 emerges fromthe distal end of the sheath and pokes through from inside to outside oftubular body organ structure 1. Centering wire 30 provides a pilot trackfor cutting catheter 40 to follow. FIG. 1a shows the distal end ofdelivery sheath 20 in the interior of a portion of tubular body organstructure 1 with a centering wire 30 piercing through from inside tooutside of the organ structure at access site 10.

[0026] The distal end of centering wire 30 is preferably deformable tofacilitate deployment and removal, but resumes its operational(preferably hooked) shape once deployed. Centering wire 30 is keptrelatively straight when it is inside sheath 20. But, when centeringwire 30 is pushed axially out the distal end of sheath 20, it curves toone side, as shown in FIGS. 1a, 1 b and 1 c. FIGS. 1b and 1 c showalternative structures for centering wire 30. In FIG. 1b, the endportion of centering wire 30 includes a selectively enlargeablestructure (such as a balloon 50 which extends annularly around theexterior of the centering wire and projects radially outwardly from thecentering wire in all radially outward directions when inflated). InFIG. 1c, the end portion of centering wire 30 includes struts 55 spacedcircumferentially around centering wire 30 and which are resilientlybiased to project from the centering wire after the end portion of thecentering wire pierces through body organ structure 1 at access site 10.By providing a selectively enlargeable structure disposed on theexterior of the centering wire at a predetermined distance proximallyfrom the distal end of the centering wire and enlarging that structureafter the centering wire has pierced organ structure 1, it is possibleto prevent the portion of centering wire 30 which is distal of theenlargeable structure from passing back into the organ structure. Inaddition to the retaining function, the enlargeable structure serves toseal the aperture and displace tissue from around the outside of organstructure 1 near access site 10, thereby creating a space. Such a spacehelps to prevent cutting head 45 from cutting other tissues afterexiting organ structure 1 at access site 10.

[0027] After piercing through organ structure 1 at access site 10 withcentering wire 30, cutting catheter 40 is passed substantially coaxiallyover the centering wire and axially along the interior of sheath 20.FIG. 2 shows cutting head 45 of cutting catheter 40 positioned forcutting at the distal end of delivery sheath 20 at access site 10.

[0028] Centering wire 30 holds cutting catheter 40 and delivery sheath20 against organ structure 1 at access site 10, thereby preventing unduebleeding during and after the creation of the aperture that could occurif the cutting catheter and the delivery sheath were to move away fromthe access site. FIG. 3 shows how the aperture is formed by advancingthe distal end of cutting catheter 40 (i.e., cutting head 45) throughfrom inside to outside of organ structure 1 at access site 10 byrotating and/or pushing the distal end of the cutting catheter.

[0029] As shown in FIGS. 2, 3, and 4, the distal end of cutting catheter40 has a circular cutting edge. Cutting catheter 40, which when advancedby rotation, cuts through tissue and removes tissue plug 60. Thepreferred embodiment of cutting head 45 also includes a serrated cuttingedge and an axially aligned recess for accepting tissue plug 60. Byremoving plug 60 of tissue (rather than merely displacing tissue, as inFIGS. 5 and 6), the elastic recoil of organ structure 1 at access site10 is reduced, which may be a desirable condition for optimal graftattachment.

[0030]FIG. 4 shows advancing the distal end of delivery sheath 20through from inside to outside of organ structure 1 at access site 10and removing centering wire 30 and cutting catheter 40 along with tissueplug 60 contained within cutting head 45.

[0031] As shown in FIG. 5, non-rotating cutting catheter 40 can be usedto create specific geometric aperture shapes (e.g., oblong aperture 70for coronary anastomosis). FIG. 5 also shows the use of the presentinvention in creating an aperture in organ structure 1 by advancing adistal end of cutting catheter 40 through from outside to inside of theorgan structure at access site 10. Centering wire 30 is tracked throughcutting catheter 40 and is shown piercing organ structure 1 at accesssite 10. Following such an outside-to-inside aperture, delivery sheath20 can be passed axially along the interior of a portion of organstructure 1 to place a distal end of delivery sheath 20 near secondaccess site 10 where an inside-to-outside aperture can be created. (Notethat organ structure 1 is shown smaller in scale relative to sheath 20and cutting catheter 40.)

[0032]FIG. 6 is a side view of organ structure 1, showing aperture 70created using non-rotating cutting catheter 40 of FIG. 5.

[0033] Cutting catheter 40 shown in FIG. 7a is a rotating catheter.Cutting head 45 could be a saw-tooth or a razor-edge type, for example.The distal end of delivery sheath 20 is shown in the interior of aportion of organ structure 1 with centering wire 30 piercing throughfrom inside to outside of the organ structure at access site 10, whereincutting catheter 40 includes dilator 80. Dilator 80 facilitatesadvancing sheath 20 through the aperture (as is shown by the successionof steps illustrated by FIGS. 7b and 7 c).

[0034] The outer diameter of dilator 80 is close to the inner diameterof sheath 20 and is typically larger than the diameter of cutting head45. As shown in FIG. 7b, as dilator 80 advances through the aperture ataccess site 10, the aperture is simultaneously sealed against bleeding.

[0035]FIG. 8 shows delivery sheath 20 which includes proximal and distalselectively enlargeable structures 90, 100. Preferably, both selectivelyenlargeable structures 90, 100 are balloons which extend annularlyaround the exterior of delivery sheath 20 and project radially outwardwhen inflated. Although the embodiment shown in FIG. 8 includes bothproximal and distal selectively enlargeable structures, either one orboth may be included. When enlarged, proximal selectively enlargeablestructure 90 prevents more than the portion of delivery sheath 20 whichis distal of the enlargeable structure from passing out of the tubularstructure via the aperture. Similarly, when enlarged, distal selectivelyenlargeable structure 100 prevents the portion of delivery sheath 20which is distal of the enlargeable structure from passing back in to thetubular structure via the aperture.

[0036] As an illustrative example of the application of the presentinvention, consider the following. Delivery sheath 20 (preferably about4.0 mm in diameter) including cutting catheter 40 is introduced intoorgan structure 1 percutaneously through the femoral artery near thethigh. Cutting catheter 40 includes cutting head 45 (preferably about3.5 mm in diameter). Delivery sheath 20 is positioned at access site 10,here the ascending aorta. Centering wire 30 is tracked through cuttingcatheter 40 and is caused to pierce the aortic artery at access site 10.Cutting catheter 40 is then tracked over centering wire 30 by eitherpushing or rotating (or a combination of both pushing and rotating) andcaused to advance through the aortic wall. An approximately 3.5 mmaperture is created with tissue plug 60 retained in cutting head 45 andremoved along with the cutting catheter 40. Delivery sheath 20 can nowbe advanced through the approximately 3.5 mm aperture created by thecutting catheter 40, causing organ structure 1 to stretch slightly(i.e., about 0.5 mm). This stretching is desirable because it provides ablood seal around delivery sheath 20 to prevent bleeding into the chestcavity. Delivery sheath 20 can now be used to introduce other catheters(including cameras, for example) from the femoral artery into the chestcavity for the purpose of diagnosis or intervention (e.g., grafts or TMRlaser surgery).

[0037] To minimize patient trauma, delivery sheath 20, cutting catheter40 and centering wire 30 are all preferably coupled to and controlled bya controller located on the outside of the patient.

[0038] Various methods and apparatus for delivering and installing plugsin walls of organ structures, as well as methods and apparatus forpromoting the closing and healing of apertures in walls of organstructures, are available (e.g., of the type shown in Goldsteen et al.U.S. Pat. No. 5,976,178; Goldsteen et al. published PCT patentapplication WO 98/47430; and Sullivan et al. published PCT patentapplication WO 98/55027, all of which are hereby incorporated byreference herein).

[0039] Thus, it is seen that a method and apparatus for creating anaperture at an access site in a patient's existing tubular body organstructure and making it possible to access specific body cavitiespercutaneously, thereby minimizing patient trauma, is provided. Oneskilled in the art will appreciate that the present invention can bepracticed by other than the described embodiments, which are presentedfor purposes of illustration and not of limitation, and the presentinvention is limited only by the claims which follow.

What is claimed is:
 1. Apparatus for cutting an aperture in a side wallof a patient's blood vessel comprising: a tissue-piercing structurehaving a longitudinal axis and being configured to pierce the side wallby passing through the side wall substantially parallel to thelongitudinal axis; a plurality of resilient structures mounted on thetissue-piercing structure so that they do not substantially increasedimensions of the tissue-piercing structure transverse to thelongitudinal axis as the tissue-piercing structure and the resilientstructures pass through the side wall, the resilient structures beingresiliently biased to spring radially outwardly from the tissue-piercingstructure after the tissue-piercing structure and the resilientstructures have passed through the side wall; and a hollow annulartissue-cutter structure disposed annularly around the tissue-piercingstructure and configured for movement substantially parallel to thelongitudinal axis and for rotation about the longitudinal axis toproduce an annular cut through the side wall and to thereby sever fromthe side wall a disc of tissue that was previously pierced by and thatremains impaled on the tissue-piercing structure, the outwardly sprungresilient structures serving to at least help hold the disc on thetissue-piercing structure.
 2. The apparatus defined in claim 1 whereinthe resilient structures are mounted on the tissue-piercing structure inan array which is annular about the longitudinal axis.
 3. The apparatusdefined in claim 1 wherein each resilient structure is mounted on thetissue-piercing structure so that the resilient structure is resilientlydeflectable substantially parallel to the longitudinal axis.
 4. Theapparatus defined in claim 1 wherein each resilient structure has adistal portion and a proximal portion, the distal portion being closerto an end of the tissue-piercing structure that is first to pass throughthe side wall, the resilient structure being secured to thetissue-piercing structure adjacent the distal portion, and the proximalportion being resiliently biased to spring radially outwardly from thetissue-piercing structure.
 5. The apparatus defined in claim 1 whereinthe tissue-cutter structure is mounted for movement relative to thetissue-piercing structure substantially parallel to the longitudinalaxis.
 6. The apparatus defined in claim 1 wherein the tissue-cutterstructure is rotatable relative to the tissue-piercing structure aboutthe longitudinal axis.
 7. The apparatus defined in claim 1 wherein thetissue-cutter structure has a serrated tissue cutting edge.
 8. Theapparatus defined in claim 1 wherein a distal portion of thetissue-piercing structure is configured to deflect transversely to thelongitudinal axis after passing through the side wall.
 9. The apparatusdefined in claim 1 wherein the tissue-cutter structure is configured tocut through the side wall in the same direction that the tissue-piercingstructure is configured to pierce through the side wall.
 10. Theapparatus defined in claim 1 wherein the tissue-cutter structure isconfigured to receive the disc in its hollow.
 11. The apparatus definedin claim 1 wherein the tissue-cutter structure has a substantiallycircular tissue cutting edge.